Only Nixon could go to China, so perhaps it is only Terry Eagleton, the irreligious British literary critic, who can stand up for theology. It has been three years now since evolutionary biologist Richard Dawkins set off the New Atheist controversies with his bestselling The God Delusion. Following him has been an eager crop of fellow nonbelieving snoots, on the one hand, and no end of pious refutations, on the other, all as polemically audacious as they are cosmically unsatisfying.

With Eagleton, though, there's a glimmer of hope. His October 2006 essay on Dawkins in the London Review of Books forged an intriguing middle ground in this usually polarized debate. Doubling the fun, Eagleton's new book, Reason, Faith, and Revolution, adds Christopher Hitchens to the dock, who apparently contributes so little to the discussion that the name "Ditchkins" suffices to encompass them both. The book's scope may be somewhat wider, but Eagleton's claim hasn't changed: "Such critics buy their rejection of religion on the cheap." When you actually bother to grasp what religious ideas mean and have meant throughout history, you'll find guillotining them to be neither so easy nor so desirable, Eagleton argues. You might even come to like them.

For reasons he assumes are obvious, Eagleton doesn't actually believe in all this stuff. And he isn't trying to get us, his intended audience of "radicals and humanists," to believe in it either. Fortunately, he received enough of a Catholic education from people who did believe to know that religion can offer "some valuable insights into human emancipation, in an era where the political left stands in dire need of good ideas." Shy of full-on belief, and therefore somewhat parasitically, he wants to keep theology around as a resource for politics.

The kind of theology he's talking about isn't what you'll get from the Falwells and Robertsons. It is Christian, but rooted in medieval metaphysicians, like Thomas Aquinas, and in the Latin American liberation theology of the last century -- sources the present pope, by the way, would insist are in flagrant contradiction. Eagleton's God is not some nosy pedant in the sky, but a disembodied artist made of infinite love and forgiveness. In Jesus Christ he sees a radical's radical, a troublemaker who commands his followers to question authority and give everything they have to the poor: "The only authentic image of this violently loving God is a tortured and executed political criminal." Eagleton's theology -- or at least the one he mimes -- stands for total commitment and fervent hope.

Yes, he writes, "religion has wrought untold misery in human affairs." But he also confesses, as Ditchkins refuses to do, that the rebellion against religion also bears responsibility for the 20th century's penchant for mass murder. Reason is capable of justifying horrors as much as it is of uncovering marvelous truths. The difference between the two lies in the kind of faith that lurks behind reason, guiding it. "Even Richard Dawkins," Eagleton quips, "lives more by faith than by reason." Theology is a conversation about the faiths and hopes that we all reason by, whether consciously or not. Better, then, to cultivate them mindfully before falling prey to dangerous fundamentalism, whether of the religious or secular variety.

Karl Marx taught that ideologies are the scaffolding that support unjust political arrangements; to unsettle an ideology, you have to disturb its political infrastructure. Eagleton carries this instinct over to the New Atheists. He calls Hitchens out for joining with the neocons to cheerlead the 2003 invasion of Iraq, and Dawkins for "oozing moral complacency." The implication is that their triumphant atheism legitimates a regime of Western hegemony. If Muslim extremists are victims of virus-like religious delusions, for instance, there is no need to restrain our violence against them or hear out their genuine political grievances. Logical arguments about the existence of God are only part of the issue, he insists; unreflective atheism today is a close cousin of unreflective militarism.

Indeed, Eagleton points out that the religion New Atheists keep attacking is one held by nobody but the most naive fundamentalists. It is literalistic, ahistorical, and without a shred of humanism. The account of Christianity that Eagleton offers is more palatable, though at the cost of passing over the miraculous magic tricks, like virgin births and multiplying fish, that are the bread and butter of popular religiosity everywhere. The Christianity on offer from Eagleton is so thin it's no wonder he feels no particular urgency to actually believe it. The tone of what he has called the "theological turn" in his writing amounts to a string of clever one-liners: "Like a hamster," Eagleton writes of God in Holy Terrors, "he is incapable of being untrue to his own nature." Or, from the new book: "Left-wing Christians are in dire need of dating agencies." As in recent beach-reads like A.J. Jacobs' Year of Living Biblically and David Plotz's Good Book, holy writ is reduced to a punch line, even if occasionally it's a profound one. All well and good, of course, but this might get in the way of getting skeptics to take theology seriously.

However much Eagleton's theological literacy may outreach Ditchkins', in the end, being able to drop a few lines from Aquinas still doesn't cut it. And he admits at the outset that what little he knows about Christian theology is still much more than he knows about any other tradition. He cites Marx and Freud almost as much as Jesus, and certainly more than Karl Barth. In this regard, Eagleton might defer to another reply to the New Atheists, released by Yale University Press on the same day and also with "revolution" in its title -- David Bentley Hart's Atheist Delusions: The Christian Revolution and Its Fashionable Enemies.

Hart, an Eastern Orthodox theologian, is one of those academics plagued by being too smart for his own good. His superhuman knowledge of the history of Christian thought, combined with a knack for body-slamming polemic, has rubbed some the wrong way. But his 2003 The Beauty of the Infinite, a profession of Christian teaching against its profoundest philosophical critics, may have already earned Hart a place of his own in the tradition he knows so well.

When Eagleton speaks of revolution, he calls to mind a pseudo-Marxist dream, admittedly betrayed by 20th-century history but still offering some hope of justice rolling down our earthly streams. Hart, though, means something rather more precise: a long, fraught process over the course of which Christianity transformed the West's idea of what it means to be human.

He tells of the great hospitals for the poor founded by early Christians, unprecedented in the pagan Roman empire; Gregory of Nyssa's sermon in 379 condemning the institution of slavery; and scriptures that audaciously claimed that a band of provincial outcasts could be apostles of God. Through the early disputes about the divine and human natures of Christ, Christian thinkers developed a "moral vision of the human person," one in which all people, regardless of social status, race, or sex, share equally in God's image and promise. Hart is not the first to contend that modern notions of universal human rights are descendants of this Christian insight. His erudition allows him to truly make the case Eagleton can only gesture at, that Christian thought is rich in resources and unique in its contributions to some of the West's most honorable ambitions for itself.

Unfortunately, Hart practices a triumphalism that distracts from the argument's force. His rosy concept of the true faith mirrors Ditchkins' concept of true reason -- one that is the cause of everything good and innocent of everything bad. After a few hundred pages of this, one starts to miss Eagleton's refreshing openness to both reasonable agnosticism and reasonable religious faith, combined with his eagerness to criticize their excesses.

Hart is at his most effecting, though, in an account of Julian the Apostate, the short-lived, fourth-century Roman emperor who tried to halt the Christianizing of the empire. Julian mounted a passionate assault on Christian theology and institutions. But the ideals he tried to assert, ultimately, had already absorbed Christianity to their core. He commanded his pagan priests to serve the poor and preach neighborly love, though their traditions provided little to draw on for such things. Hart writes that "everything Julian wanted from his chosen faith -- personal liberation and purification, a united spiritual culture, a revived civilization, moral regeneration for himself and his people -- was possible only through the agency in time of the religion he so frantically despised."

The New Atheists should remember Julian before thinking our religious heritage can be done away with so easily. Often the very standards by which they judge religion -- consistency, tolerance, and universal truth, for instance -- have roots in that heritage. (Richard Dawkins has the sense to call himself a post-Christian atheist.) Eagleton, too, might think twice about the prospects of domesticating theology as stock material for his political agenda. Just when you think you've got religion under control, you may find that it has got you.